The musculoskeletal system: muscle

Abstract

Ageing of the muscular system is a central part of the ageing process and is associated with mortality, morbidity frailty and disability. Skeletal muscle is the most abundant tissue in the human body and the changes that occur with advancing age constitute a significant part of the general ageing process. Skeletal muscle is essential for posture and movement as well as being central to metabolic processes and thermoregulation. The two most common causes of age-related muscle loss are sarcopenia and cachexia. Sarcopenia, which occurs universally, is the unintentional loss of muscle mass and function that occurs with age. Cachexia is a complex metabolic syndrome associated with sustained inflammation and characterised by the loss of muscle mass with or without loss of fat mass. Loss of skeletal muscle mass is directly associated with ageing and individuals who lose muscle mass at greater rates experience increased morbidity and mortality and reduced independence and quality of life.